The present invention relates generally to variable geometry aircraft and more particularly to an extensible and retractable wing for aircraft.
In the field of aeronautics those concerned with improving the flight characteristics of aircraft have employed variable sweep wings, telescoping wings, and folded wing tip designs. These arrangements allow the aircraft configuration to be designed for high-speed, cruise flight, while still providing satisfactory landing, take-off, and maneuvering characteristics at lower speeds of the aircraft.
Some extensible wing designs employed in the past used semi-spans which consisted of a main inner wing section permanently affixed to the fuselage and a retractable wing telescopically mounted in the main inner wing. These cantilevered wing constructions produced extremely high maximum loads at the movable wing root for extended positions of the wings. Moreover, extensive gearing arrangements were required to be incorporated into the main wings to support the separate retractable wings. These necessities required a relatively heavy and complex mechanical structure.
In the case of a variable geometry aircraft in which the wing sweep angle is varied, high wing loads also exist. In addition, variation of the sweep angle causes the neutral point of the aircraft to move and creates certain aerodynamic problems.